Objective: To study the mechanism of “Shuanggu Yitong” acupuncture therapy in the treatment of postmenopausal osteoporosis (PMO). Methods: A total of 60 female SD rats (aged 9-10 months) were randomized into control group

routine-acupoint group “Pishu” (BL 20)

“Weishu”(BL 21)

“Shenshu”(BL 23) and “Qihaishu”(BL 24)

“Shuanggu” group “Guanyuan”(RN 4) and “Zusanli”(ST 36)

“Yitong” group “Shenshu”(BL 23)

“Geshu”(BL 17) and “Dazhu”(BL 11)

and “Shuanggu Yitong” group “Guanyuan”(RN 4)

“Zusanli”(ST 36)

“Shenshu”(BL 23)

“Geshu”(BL 17) and “Dazhu”(BL 11)

with 12 cases in each group. PMO model was established by removing the bilateral ovaries and fed normally for 90 days. Electroacupuncture (EA

8- 20 Hz

about 1 mA ) was respectively applied to the aforementioned acupoints for 15 min

once a day and continuously for 8 weeks. The interval between every 6 days' treatments was one day. At the end of the study

the rats were deeply anesthetized and killed for taking out the right tibial tissue which was cut into sections (10 μm). The expression of osteoprotegerin (OPG) mRNA was assayed by using reversed transcription-polymerase chain reaction (RT-PCR) technique. Results: Compared with model control group

the expression levels of OPG mRNA in the 4 acupuncture groups were all up-regulated significantly (P<0.05)

and the integral value of the absorbed optical density of “Shuanggu Yitong” group was significantly higher than those of routine-acupoint group

“ Shuanggu” group and “Yitong” group (P<0.05). No significant differences were found among routine-acupoint group

“Shuanggu” group and “Yitong” group (P>0.05). Conclusion: Acupuncture can up-regulate the expression level of OPG mRNA in osteoporosis rats

and the effect of “Shuanggu Yitong” group is markedly superior to that of routine-acupoint acupuncture

“Shuanggu” and “Yitong” groups.